Wednesday, September 05, 2018

The double and triple chain ring drive train set ups that many are eschewing these days are, in my opinion, misunderstood, unfairly maligned, and have benefits for certain applications that outweigh their negatives. To be sure, I have tried and use 1X set ups. So, please do not read this as a "1x's are a bad thing and should go away" post. It isn't that at all. But on the other hand, 2X and 3X have a place, and they shouldn't go away either.

A little over a year ago now I wrote this post about some new ideas Shimano and SRAM patented which would address some inefficiencies inherent in 1X drive train set ups. That points up the fact that whenever you move to innovate in one area of bicycle design, you will in turn compromise something else. There is never any free lunch, it seems, no "win-win" situations. Something gets presented as a benefit but some other area suffers.
In my opinion, this is due mostly to the fact that in the late 19th and early 20th Centuries, the bicycle's mechanical properties were honed to a point where the efficiencies and mechanical properties, at least on paper, were optimized to their furthest extent. Consider the lowly chain. Nothing- not even belt driven drive trains-in real world use have been proven to be more efficient. There are many more examples of this which I could share. So, when we tweak out one area of the system, some other part suffers. We are tinkering with a device that was honed to its zenith over a 100 years ago.

SRAM's solution involves an articulating chain ring system.

So, 1X has inefficiencies having to do with chain line. The most efficient chain line is "dead straight" from one cog to another, front to back. In other words, think "single speed" chain line. Derailleurs, by their very nature, introduce an inefficiency merely by the fact that the chain line has to deflect from straight to accommodate using multiple cogs out back. The more the chain goes sideways, the less efficient the mechanism becomes. This was a compromise introduced in the early 20th Century and has reached its zenith now with 1X 12 systems and their sibling 11 and 10 speed variations.

The public perception is that "front derailleurs are bad", so marketing has asked R&D to solve the inefficiency issues with these patented ideas being shown again today on the blog. Now, I want you to consider, if you will, what this would look like: Imagine there had never been a front derailleur before. Let's say one was introduced tomorrow. I guarantee we would all be ditching 1X in a heart beat. Why? Because with a front derailleur, we could keep our chain lines more straight, and thus- more efficient use of our energy would result. But that isn't what happened.

Instead, we have forgotten that 2X and 3X drive trains require skill and understanding to operate efficiently. To be sure, we have the very best front derailleurs we've ever been able to get now days. We have the very best chain rings to allow for front shifting to happen. We have the best chains we've ever been able to get for front shifting. That doesn't matter. We still see 1X road and gravel set ups being touted as "better". 1X MTB for everyone is thought to be "better". I'm saying it isn't always better, and it is mostly due to marketing and that people don't understand multiple front ring drive trains.

9 comments:

I think 1x is great for commuter bikes and bikes that never get too far from home. I've used that set up for over 20 years now, long before it was "cool". But what about Rando,Touring or Bikepacking. If you bork your only chainring out in the sticks you're in for a long walk home.

Agree, GTed, but I would also add cyclocross along with mountain to the areas where 1x is probably better. Those bigger jumps on the cassette help with the rapid changes in speed. But for road, gravel, etc.... 2x all the way!

Hey,GT,where can I get one of those new-fangled, front der... whatchamacallits?

Kidding aside, the comment against fd's I find the most ridiculous is "I want one less thing to think about when I ride." Sheesh, what is there to think about? I pretty much stay in my small ring for trail riding. When I get to a fire road or a long, open stretch of trail, guess what?, I have a larger ring to shift up to pedal faster and more efficiently. XT 2x11 never lets me down. Neither does the SRAM 2x10 on my other bike. It just works.

I'm still a big fan of 2X setups, even for mountain bike racing. When you go over that steep hill in your 24-36 and can quickly change to the 36 up front when you get to the top of the hill it's a much quicker and efficient transition. And the newer Shimano side pull front derailleurs are so good.

Agree that 1X has its place, and is fine for those who like it, or where a suspension design might preclude a front derailleur. The problem seems to be that many bike companies are pushing 1X, under the guise of being "better", merely to take some cost out of their bikes. You can even see them touting their 1X drive train as being 2X compatible. Well thanks a bunch! After I've already shelled out to buy the bike, I now have to add the shifter and 2nd chainring myself, at further expense.

Personally, you can take the triple setup off my randonneuring bike when you pry it out of my cold, dead hands.

I couldn't agree more. I, too, have been single speeding and 1x-ing my own bikes far before it was a "thing"....but not all of them. My randonneur bike and classic touring and mountain bikes have triples up front because it's nicely suited for the type of riding that I do on them....just as the spec managers intended them to be. As a guy who works the sales floor of a bike shop, it seems to me that over the last few years, customers come in looking for whatever the latest feature is that they've seen on the internet, with the intention of buying it for the wrong reason. There are days when all I seem to do is tell people that lockouts are not a substitute for a rigid fork, 1x is NOT "the way to go" on everything, and that fatbikes are not slow, heavy and hard to pedal, nor are they "snow bikes". At any rate, despite this it's still a fun gig.

I still ride 3× bikes on a regular basis. The middle ring is a comfortable home base, while I can still count on the little ring in case I'm surprised by a steep hill. I almost never use the big ring unless I'm going downhill.

All this said, this is while carrying three bags on my bike as I usually do.